Unified system for authentication and authorization

ABSTRACT

A request is received from a trusted application to authorize a client application that requests a service offered by the trusted application. In view of the request, it is determined whether the client application is authorized to access the trusted application in view of an authorization policy. An authentication of a user of the client application is caused in response to determining the client application is authorized to access the trusted application. An authorization result is returned to the trusted application in view of the determining and the authentication.

RELATED APPLICATIONS

The present application is a continuation of U.S. patent applicationSer. No. 12/613,980 filed Nov. 6, 2009, which is incorporated byreference herein.

TECHNICAL FIELD

The present invention relates generally to security of data processingsystems. More particularly, this invention relates to a unified systeminterface for authentication and authorization.

BACKGROUND

Traditionally operating systems, such as a UNIX operating system (OS),have a clear distinction between ordinary unprivileged users and thepowerful super user with a “root” privilege. However, in order for auser to access and configure hardware additional privileges and rightsare needed. This has been done in a number of often OS-specific ways.For example, some systems usually grant access to devices to a user if,and only if, the user is logged in at a local console. In contrast,other systems often relies on group membership, e.g. users in the“cdrom” group can access optical drives; users in the “plugdev” groupcan mount removable media; and so on.

Traditionally, authentication and authorization are two distinctiveprocesses that require separate processing entities. There has been alack of an efficient way for authenticating and authorizing a usersession for accessing a privileged application.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention is illustrated by way of example and notlimitation in the figures of the accompanying drawings in which likereferences indicate similar elements.

FIG. 1 is a block diagram illustrating a system having an authorizationframework according to one embodiment.

FIGS. 2A-2B are screenshots illustrating a graphical user interface forauthenticating a user.

FIG. 3 is a flow diagram illustrating a method for authorizing access ofa privileged application according to one embodiment.

FIG. 4 illustrates a diagrammatic representation of a machine in theexemplary form of a computer system which may be used with an embodimentof the invention.

DETAILED DESCRIPTION

In the following description, numerous details are set forth to providea more thorough explanation of the embodiments of the present invention.It will be apparent, however, to one skilled in the art, thatembodiments of the present invention may be practiced without thesespecific details. In other instances, well-known structures and devicesare shown in block diagram form, rather than in detail, in order toavoid obscuring embodiments of the present invention.

Reference in the specification to “one embodiment” or “an embodiment”means that a particular feature, structure, or characteristic describedin connection with the embodiment is included in at least one embodimentof the invention. The appearances of the phrase “in one embodiment” invarious places in the specification do not necessarily all refer to thesame embodiment.

According to some embodiments, an interface is provided for privilegedor trusted applications to access an authorization framework indetermining whether a particular client (e.g., untrusted application)communicating with the privileged/trusted application can access aservice provided by the privileged/trusted application. The actualdecision-making process (e.g., authorization and/or authentication) ishidden from the privileged/trusted application. In authorizing a client,one implementation could read authorization policy from a local disk andanother implementation could read authorization policy from a trusteddirectory server over a network, dependent upon a specificconfiguration. In addition, an authentication interface is provided toallow a user to gain temporary authorization by authenticating the useritself or as an administrator or a super user. Thus, the authorizationframework is implemented combining the functionalities of authorizationand authentication in a unified application programming interface (API),which is may be implemented as an inter-process call (IPC) or system busmessage mechanism (e.g., D-bus or UNIX pipes).

FIG. 1 is a block diagram illustrating a system having an authorizationframework according to one embodiment. For example, system 100 may be aclient computer (e.g., desktop or laptop) or a server computer.Referring to FIG. 1, according to one embodiment, system 100 includes anauthorization framework 101 to be accessed by a privileged or trustedapplication 102 via an authorization API, which may be implemented as apart of IPC or system bus mechanism (e.g., D-bus or UNIX pipes).Privileged/trusted application 102 may be any system component that istrusted by the system 100, which is running within the trusted systemcontext. For example, privileged/trusted application 102 may be providedby an operating system vendor or alternatively, a third partyapplication that is certified by the operating system vendor.Privileged/trusted application 102 may provide a service or services(e.g., mounting a disk drive) to an unprivileged application 103 as aclient within system 100 or alternatively, application 103 may be anapplication running at a remote host communicatively coupled to thesystem 100.

In one embodiment, when client 103 communicates with privilegedapplication 102 for accessing a service provided by the privilegedapplication 102, privileged application 102 communicates withauthorization framework 101 to determine whether client 103 isauthorized for accessing the requested service. In response,authorization unit 107 is configured to authorize client 103 in view ofone or more policies stored in the authorization database 104. Theauthorization database 104 may be implemented in one or more databasesand stored in a storage device 105, which may be located locally orremotely over a network.

When privileged/trusted application 102 communicates with authorizationframework 101, certain information for identifying client 103 may alsobe communicated to the authorization framework 101, such as, forexample, a user identifier (ID) identifying a user of a clientapplication, a process ID identifying a client application, a session IDidentifying a user or desktop session within which the clientapplication is running, and/or an action ID identifying an action to becarried out by the privileged/trusted application 102. Certain OSspecific attributes such as security context may also be included. Basedon such information, authorization unit 107 examines one or morepolicies stored in authorization database 104 in order to determinewhether client 103 is authorized to access a particular service (e.g.,action) carried out by the privileged/trusted application 102. Thetrusted application 102 may have registered or declared certain actionsand the required privileges associated with the actions with theauthorization framework, which may be stored in the authorizationdatabase 104.

The result of the authorization process may be a “yes” which indicatesthat the requested action should be carried out by the trustedapplication 102. Alternatively, the result of the authorization processmay be a “no” which indicates that the requested action should not becarried out by the trusted application 102. Further, the result of theauthorization process may be an “authentication required” whichindicates that the requested action should only be carried out by thetrusted application 102 if the user of the client application has beensuccessfully authenticated. According to one embodiment, theprivileged/trusted application 102 may specify or include an attributeindicating whether a user interaction is allowed. If no user interactionis allowed, there is no authentication happened and only in thissituation will it receives the “authentication required” result.However, if the user interaction is allowed, it may not receive the“authentication required” result, but the authentication determinationperformed on the authorization framework 101 could take a relativelylong period of time. According to one embodiment, the privileged/trustedapplication 102 can also cancel or terminate the authorizationdetermination process performed via the authorization framework 101 ifsuch a process takes too long.

If it is determined that client 103 is authorized to access therequested service, but would require authentication, authorizationframework further determines whether a user associated with client 103should be authorized to access the requested services by authenticatingthe user. In some situations, a client machine can be a workstation thatis shared by multiple users with different privileges (e.g., regularuser, super user, or administrator privilege). If it is determined thatthe user of client 103 needs to be authenticated, authentication unit108 invokes an authentication agent 106 which is running within the sameuser session of client 103, which may be identified by a session ID.Authentication agent 106 may display a dialog box, such as dialog boxesas shown in FIGS. 2A-2B, for prompting the user to enter certaincredentials to authenticate the user itself. Based on the credentialsentered by the user, authentication unit 108 is configured toauthenticate the user in view of authentication information stored indatabase 104. If the user is successfully authenticated, authorizationframework 101 returns a value to privileged/trusted application 102indicating whether the requested service is authorized to be carried outby the privileged/trusted application 102. Note that authorizationframework 101 may be a core component of an operating system runningwithin system 100. Note that the authentication agent 106 can run on acompletely separate device communicatively coupled to system 100 via acommunication link, wired or wireless. For example, an authenticationagent may be a separate device having a small display and a button (e.g,cellular phone) that is coupled to system 100 via a universal serial bus(USB) connection. In some situations, the authentication agent isdesigned to not require a password—merely pressing a single button wouldbe sufficient for authentication. In other situations, it may ask forpasswords or other kinds of authentication (e.g., checking fingerprint,etc.) Also note that although authentication agent 106 is related to auser session, it may not necessarily be part of the user session ofclient 103. The authentication agent 106 can serve one or more usersessions.

In addition, authorization framework 101 includes one or more extensioninterfaces 109 to allow third-party vendors and/or sites to implementcertain extensions to further control authorization policies. Forexample, a third-party authority may be authorization framework 110implemented either locally (as part of computer system 100) or remotely(as part of a different computer system) over network 111, which may bea local area network (LAN), a wide area network (WAN), or a combinationof both LAN and WAN.

Thus, authorization framework 101 provides an authorization API to beused by privileged/trusted application 102 offering services tounprivileged application 103 through some forms of IPC mechanisms suchas D-bus or UNIX pipes. The privileged application 102 typically treatsclient 103 as an untrusted application. For every request received fromclient 103, privileged/trusted application 102 needs to determine if therequest is authorized or privileged/trusted application 102 shouldrefuse to service client 103. By using the authorization API,privileged/trusted application 102 can offload the authorization and/orauthentication process to authorization framework 101.

In addition to acting as an authority, authorization framework 101allows a user to obtain a temporary authorization through authenticatingeither an administrator or an owner of the user session associated withclient 103. This is useful for scenarios where a privileged/trustedapplication needs to verify that the operator of client 103 really isthe user or really is an administrator. Authentication agent 106 is usedto request a user of a user session to prove that the user of thesession really is the user (by authenticating as the user) or anadministrative user (by authenticating as an administrator).

In one embodiment, authentication agent 106 may provide a graphical userinterface (GUI) as shown in FIGS. 2A-2B. Referring to FIG. 2A, GUI 200is designed to inform a user in a message 201 that an application isattempting to perform an action that requires privileges and the userhas to be authenticated as a super user by entering a passwordassociated with a super user in field 202 for the purpose ofauthenticating the user. Alternatively, as shown in FIG. 2B, if thesystem is configured without a “root” account, GUI 250 may be used toallow a user to select one of the predetermined users in field 251 andto enter an associated password in field 252 for the purpose ofauthenticating the user.

Components 101-102 can be implemented as core components of an operatingsystem (OS). Component 102 may be a third party application that iscertified by a vendor of the operating system running within system 100.Authentication can be specified (in a return value) as either userauthentication (e.g., user enters its own password) or super userauthentication (e.g., user enters the root password or a user in anadministrator group authentication). The authorization can bemaintained: 1) indefinitely (e.g., it persists across multiple usersessions or reboot); 2) for the remainder of the desktop session; and 3)within a period of time (e.g., a life-time of a particular process).Note that some or all of the components as shown in FIG. 1 may beimplemented in software, hardware, or a combination of both.

FIG. 3 is a flow diagram illustrating a method for authorizing access ofa privileged application according to one embodiment. Note that method300 may be performed by processing logic which may include software,hardware, or a combination of both. For example, method 300 may beperformed by authorization framework 101 of FIG. 1. Referring to FIG. 3,at block 301, a request is received via an authorization API from atrusted application for authorizing a client application for access aservice provided by the trusted application. In response to the request,at block 302, an authorization unit determines whether the clientapplication is authorized to access the trusted application in view ofpolicies. If authentication is needed, at block 303, an authenticationunit invokes an authentication agent associated with a user session ofthe client application via a system API to request a user to enter thenecessary credentials to authenticate the user (e.g., either a superuser or an administrator). Based on the credentials entered, at block304, the user is authenticated and at block 305, the authorizationframework returns a value to the trusted application indicating whetherthe client/user is authorized for accessing the service provided by thetrusted application.

FIG. 4 illustrates a diagrammatic representation of a machine in theexemplary form of a computer system 800 within which a set ofinstructions, for causing the machine to perform any one or more of themethodologies discussed herein, may be executed. In alternativeembodiments, the machine may be connected (e.g., networked) to othermachines in a LAN, an intranet, an extranet, and/or the Internet. Themachine may operate in the capacity of a server or a client machine inclient-server network environment, or as a peer machine in apeer-to-peer (or distributed) network environment. The machine may be apersonal computer (PC), a tablet PC, a set-top box (STB), a PersonalDigital Assistant (PDA), a cellular telephone, a web appliance, aserver, a network router, a switch or bridge, or any machine capable ofexecuting a set of instructions (sequential or otherwise) that specifyactions to be taken by that machine. Further, while only a singlemachine is illustrated, the term “machine” shall also be taken toinclude any collection of machines that individually or jointly executea set (or multiple sets) of instructions to perform any one or more ofthe methodologies discussed herein.

The exemplary computer system 800 includes a processing device 802, amain memory 804 (e.g., read-only memory (ROM), flash memory, dynamicrandom access memory (DRAM) such as synchronous DRAM (SDRAM), etc.), astatic memory 806 (e.g., flash memory, static random access memory(SRAM), etc.), and a data storage device 816, which communicate witheach other via a bus 808.

Processing device 802 represents one or more general-purpose processingdevices such as a microprocessor, a central processing unit, or thelike. More particularly, the processing device may be complexinstruction set computing (CISC) microprocessor, reduced instruction setcomputing (RISC) microprocessor, very long instruction word (VLIW)microprocessor, or processor implementing other instruction sets, orprocessors implementing a combination of instruction sets. Processingdevice 802 may also be one or more special-purpose processing devicessuch as an application specific integrated circuit (ASIC), a fieldprogrammable gate array (FPGA), a digital signal processor (DSP),network processor, or the like. The processing device 802 is configuredto execute the instructions 101 for performing the operations and stepsdiscussed herein.

The computer system 800 may further include a network interface device822. The computer system 800 also may include a video display unit 810(e.g., a liquid crystal display (LCD) or a cathode ray tube (CRT)), analphanumeric input device 812 (e.g., a keyboard), a cursor controldevice 814 (e.g., a mouse), and a signal generation device 820 (e.g., aspeaker).

The data storage device 816 may include a computer-accessible storagemedium 824 (also known as a machine-readable storage medium or acomputer-readable medium) on which is stored one or more sets ofinstructions or software (e.g., authorization framework 101) embodyingany one or more of the methodologies or functions described herein. Theauthorization framework 101 may also reside, completely or at leastpartially, within the main memory 804 and/or within the processingdevice 802 during execution thereof by the computer system 800, the mainmemory 804 and the processing device 802 also constitutingmachine-accessible storage media. The authorization framework 101 mayfurther be transmitted or received over a network via the networkinterface device 822.

The computer-readable storage medium 824 may also be used to store theauthorization framework 101 persistently. While the computer-readablestorage medium 824 is shown in an exemplary embodiment to be a singlemedium, the term “computer-readable storage medium” should be taken toinclude a single medium or multiple media (e.g., a centralized ordistributed database, and/or associated caches and servers) that storethe one or more sets of instructions. The terms “computer-readablestorage medium” shall also be taken to include any medium that iscapable of storing or encoding a set of instructions for execution bythe machine and that cause the machine to perform any one or more of themethodologies of the present invention. The term “computer-readablestorage medium” shall accordingly be taken to include, but not belimited to, solid-state memories, and optical and magnetic media.

The modules 828, components and other features described herein can beimplemented as discrete hardware components or integrated in thefunctionality of hardware components such as ASICS, FPGAs, DSPs orsimilar devices. In addition, the modules 828 can be implemented asfirmware or functional circuitry within hardware devices. Further, themodules 828 can be implemented in any combination hardware devices andsoftware components.

In the above description, numerous details are set forth. It will beapparent, however, to one skilled in the art, that the present inventionmay be practiced without these specific details. In some instances,well-known structures and devices are shown in block diagram form,rather than in detail, in order to avoid obscuring the presentinvention.

Some portions of the preceding detailed descriptions have been presentedin terms of algorithms and symbolic representations of operations ondata bits within a computer memory. These algorithmic descriptions andrepresentations are the ways used by those skilled in the dataprocessing arts to most effectively convey the substance of their workto others skilled in the art. An algorithm is here, and generally,conceived to be a self-consistent sequence of operations leading to adesired result. The operations are those requiring physicalmanipulations of physical quantities. Usually, though not necessarily,these quantities take the form of electrical or magnetic signals capableof being stored, transferred, combined, compared, and otherwisemanipulated. It has proven convenient at times, principally for reasonsof common usage, to refer to these signals as bits, values, elements,symbols, characters, terms, numbers, or the like.

It should be borne in mind, however, that all of these and similar termsare to be associated with the appropriate physical quantities and aremerely convenient labels applied to these quantities. Unlessspecifically stated otherwise as apparent from the above discussion, itis appreciated that throughout the description, discussions utilizingterms such as “receiving” or “authorizing” or “authenticating” or“returning” or “invoking” or the like, refer to the action and processesof a computer system, or similar electronic computing device, thatmanipulates and transforms data represented as physical (electronic)quantities within the computer system's registers and memories intoother data similarly represented as physical quantities within thecomputer system memories or registers or other such information storage,transmission or display devices.

Embodiments of the present invention also relate to an apparatus forperforming the operations herein. This apparatus may be speciallyconstructed for the required purposes, or it may comprise ageneral-purpose computer selectively activated or reconfigured by acomputer program stored in the computer. Such a computer program may bestored in a computer readable medium. A machine-readable medium includesany mechanism for storing or transmitting information in a form readableby a machine (e.g., a computer). For example, a machine-readable (e.g.,computer-readable) medium includes a machine (e.g., a computer) readablestorage medium (e.g., read only memory (“ROM”), random access memory(“RAM”), magnetic disk storage media, optical storage media, flashmemory devices), etc.

The algorithms and displays presented herein are not inherently relatedto any particular computer or other apparatus. Various general-purposesystems may be used with programs in accordance with the teachingsherein, or it may prove convenient to construct more specializedapparatus to perform the required method operations. The requiredstructure for a variety of these systems will appear from thedescription above. In addition, embodiments of the present invention arenot described with reference to any particular programming language. Itwill be appreciated that a variety of programming languages may be usedto implement the teachings of embodiments of the invention as describedherein.

In the foregoing specification, embodiments of the invention have beendescribed with reference to specific exemplary embodiments thereof. Itwill be evident that various modifications may be made thereto withoutdeparting from the broader spirit and scope of embodiments of theinvention as set forth in the following claims. The specification anddrawings are, accordingly, to be regarded in an illustrative senserather than a restrictive sense.

What is claimed is:
 1. A method of performing an authorization foraccess to a service offered by a trusted application comprising:receiving, by an authorization framework executed by a processingdevice, a request from the trusted application to authorize a clientapplication that requests the service offered by the trustedapplication, wherein the request identifies the client application andan action to be carried out by the trusted application; determining, inview of the request, whether the client application is authorized toaccess the trusted application in view of an authorization policy;causing an authentication of a user of the client application inresponse to determining the client application is authorized to accessthe trusted application; and returning, by the authorization frameworkand to the trusted application, an authorization result in view of thedetermining and the authentication that indicates to the trustedapplication whether to offer the client application the service andwhether to carry out the action.
 2. The method of claim 1, wherein thetrusted application is a software application to offer the service tothe client application, and wherein the service requested by the clientapplication is other than authorization and authentication.
 3. Themethod of claim 1, wherein the request identifies the user of the clientapplication.
 4. The method of claim 1, wherein causing theauthentication of the user comprises invoking an authentication agent tocollect one or more credentials from the user that are used to accessthe service.
 5. The method of claim 4, wherein the user accesses theclient application within a session, and wherein the authenticationagent runs in the session.
 6. The method of claim 4, wherein the useraccesses the client application within a session, and wherein theauthentication agent runs outside the session.
 7. The method of claim 4,wherein the one or more credentials comprise a fingerprint.
 8. Themethod of claim 4, wherein the authentication agent is to display agraphical user interface to obtain the one or more credentials from theuser, and wherein the one or more credentials comprise a credentialassociated with a super user that is used to access the service.
 9. Themethod of claim 4, wherein the authentication agent is to display agraphical user interface that enables the user to select a predeterminedauthorized user and a credential associated with the predeterminedauthorized user that is used to access the service.
 10. The method ofclaim 1, further comprising accessing a different authority to performat least one of additional authorization of the client application oradditional authentication of the user.
 11. A non-transitorycomputer-readable medium comprising instructions that, responsive toexecution by a processing device, cause the processing device to performoperations comprising: receiving, by an authorization framework executedby the processing device, a request from a trusted application toauthorize a client application that requests a service offered by thetrusted application, wherein the request identifies the clientapplication and an action to be carried out by the trusted application;determining, in view of the request, whether the client application isauthorized to access the trusted application in view of an authorizationpolicy; causing an authentication of a user of the client application inresponse to determining the client application is authorized to accessthe trusted application; and returning, by the authorization frameworkand to the trusted application an authorization result in view of thedetermining and the authentication that indicates to the trustedapplication whether to offer the client application the service andwhether to carry out the action.
 12. The non-transitorycomputer-readable medium of claim 11, wherein the trusted application isa software application to offer the service to the client application,and wherein the service requested by the client application is otherthan authorization and authentication.
 13. The non-transitorycomputer-readable medium of claim 11, wherein the request identifies theuser of the client application.
 14. The non-transitory computer-readablemedium of claim 11, wherein causing the authentication of the usercomprises invoking an authentication agent to collect one or morecredentials from the user that are used to access the service.
 15. Thenon-transitory computer-readable medium of claim 14, wherein the useraccesses the client application within a session, and wherein theauthentication agent runs outside the session.
 16. The non-transitorycomputer-readable medium of claim 14, wherein the one or morecredentials comprise a fingerprint.
 17. A system to perform anauthorization for access to a service offered by a trusted applicationcomprising: a memory; and a processing device, operatively coupled tothe memory, to: receive, by an authorization framework executed by theprocessing device, a request from the trusted application to authorize aclient application that requests the service offered by the trustedapplication, wherein the request identifies the client application andan action to be carried out by the trusted application; determine, inview of the request, whether the client application is authorized toaccess the trusted application in view of an authorization policy; causean authentication of a user of the client application in response todetermining the client application is authorized to access the trustedapplication; and return, by the authorization framework and to thetrusted application, an authorization result in view of the determiningand the authentication that indicates to the trusted application whetherto offer the client application the service and whether to carry out theaction.
 18. The system of claim 17, wherein the request identifies theuser of the client application.
 19. The system of claim 17, wherein tocause the authentication of the user, the processing device to invoke anauthentication agent to collect one or more credentials from the userthat are used to access the service, and wherein the authenticationagent runs outside a session that the user uses to access the clientapplication.
 20. The system of claim 19, wherein the one or morecredentials comprise a fingerprint.